We examined the disassembly of the engine in the article - "How to disassemble the ZMZ-402 engine".

There we looked at how to remove the crankshaft.

Consider how to disassemble the crankshaft itself and defect.

Before disassembling the crankshaft, rinse it with gasoline and dry it.

Inspect the crankshaft. If it has cracks or severe seizures, then the crankshaft cannot be repaired.

We disassemble the crankshaft for both replacement and boring.

Разборка и дефектовка коленчатого вала ЗМЗ-402 Разборка и дефектовка коленчатого вала ЗМЗ-402

Using a three-fingered puller, we press the drive gear together with a thrust washer

There is a chamfer on the thrust washer, during assembly it is necessary that the chamfer is installed to the counterweight of the crankshaft

Разборка и дефектовка коленчатого вала ЗМЗ-402Разборка и дефектовка коленчатого вала ЗМЗ-402

Use a thin chisel to knock out the pinion key

Remove the thrust washers limiting the axial movement of the crankshaft

The front washer is kept from turning by two pins.

Разборка и дефектовка коленчатого вала ЗМЗ-402Разборка и дефектовка коленчатого вала ЗМЗ-402

One pin is installed in the block, and the second on the cover of the first main bearing

We install the rectangular protrusion of the rear washer into the groove on the other side of the cover of the first main bearing

If there are minor risks on the main and connecting rod journals, scratches, galls or ovality of the journals exceeds 0.01 mm, the journals must be sanded to the repair size.

After grinding, the neck must be polished.

Dull sharp edges of oil channel chamfers with an abrasive taper.

Repair dimensions of the shaft journals are given in the table.

Nominal and maximum permissible dimensions of the motor mod. 402

Номинальные и предельно допустимые размеры двигателя мод. 402

Landing of mating parts of the crankshaft

Name

details


 

Clearance, mm

Tension, mm

min

max

min

max

 

 

 

 

 

 

 

 

Cranked

shaft

0,02

0,073

__

1-

repair

the size


0,02

1-

repair

the size


0,073

1-

the size

   —

1-

the size

2-

repair

the size

0,02

2-

repair

the size

0,073

2-

the size

   __

2-

the size

   __

3-

repair

the size

0,02

3-

repair

the size

0,073

3-

the size

   __

  3-

the size

   __

Cranked

shaft


 

0,01

0,063

1-

repair

the size

0,01

1-

repair

the size

0,063

1-

the size  __

1-

the size

_

2-

repair

the size

0,01

2-

repair

the size

0,063

2-

the size

   __

2-

the size

   __

3-

repair

the size

0,01

3-

repair

the size

0,063

   3-

the size

   __

3-

the size

   __

Bearing

sock

primary

gearbox shaft

0,001

 

0,028

Flywheel

0

0,068

Flywheel

0,39

0,64

Cranked

shaft

0,125

0,325

Cranked

shaft

0,04

0,004

Pulley

crankshaft

0

0,12

Cranked

shaft

0,018

0,027

Cranked

shaft

0,053

0,241

After boring, unscrew the crankshaft channel plugs. We flush the channels with diesel fuel or kerosene and blow them with compressed air.

Разборка и дефектовка коленчатого вала ЗМЗ-402Разборка и дефектовка коленчатого вала ЗМЗ-402

We wrap the plugs and tighten with a torque of 38–42 N · m (3.8–4.2 kgf · m)

Cut out the edges of the plugs with a beard

After grinding the crankshaft journals, install the main and connecting rod bearing shells of the appropriate repair size.

Inspect the main bearing shells. If they have risks, seizures, scratches, delamination, inclusions of solid particles, etc., replace the liners.

Inspect flywheel.

If the flywheel ring teeth are damaged, there are seizures, scratches, etc. on the surface adjacent to the clutch disc, replace the flywheel.

If the flywheel is cracked, it must also be replaced.

Разборка и дефектовка коленчатого вала ЗМЗ-402

Inspect the crankshaft oil seal in the camshaft cover.

If the oil seal is damaged (tears, tears, large wear of the working edge, etc.), it must be removed from the cover with a screwdriver and a new one pressed in.

When the vehicle is mileage, it is recommended to replace the oil seal.

Разборка и дефектовка коленчатого вала ЗМЗ-402

Replace the crankshaft rear seal packing in the main bearing bed and in the holder.

Remove the old packing and insert a new one approximately 120 mm long.

Cut the ends of the packing so that it protrudes above the plane of the bed and the holder by 0.5–1.0 mm (This is done if there is packing on the engine, if the oil seal does not need to be performed, the oil seal must be replaced).

Разборка и дефектовка коленчатого вала ЗМЗ-402

Crimp the packing, to do this, lay the mandrel 1 in the bearing bed, install the holder 4 and the main bearing cap and tighten the nuts 3 and bolts 2.

Разборка и дефектовка коленчатого вала ЗМЗ-402

The illustration shows the dimensions of the mandrel for crimping the crankshaft packing.

Разборка и дефектовка коленчатого вала ЗМЗ-402Разборка и дефектовка коленчатого вала ЗМЗ-402

Replace rubber seals 1 (flags).

The bearing of the toe of the input shaft, closed type, is pressed into the bore of the crankshaft from the flywheel side.

Inspect the bearing, if any defects are found (large play, jamming, damage to protective rings, etc.), press it out of the crankshaft using a puller.

Press in the new bearing flush with the bottom edge of the chamfer of the bore in the crankshaft.